This invention deals generally with the collection and discharge of exhaust gases from motor vehicles operating within a building, and more specifically with an exhaust control system installed aboard a vehicle which automatically switches over from the building exhaust system to the normal vehicle exhaust system when the vehicle is moved from the building.
The requirement that motor vehicle exhaust gases be removed from any enclosure within which a vehicle is operating is quite obvious since the carbon monoxide emitted from a vehicle exhaust is toxic. The existing devices to accomplish the direct discharge of such vehicle exhaust gases to the outside of the building are quite varied. They include everything from a simple flexible hose slipped over the tail pipe and through a hole in a garage door to multiple stations with blower driven exhaust ducts to which flexible hoses are attached for connection to the vehicles' exhaust pipes.
These vehicle exhaust systems for buildings all have one thing in common. They are all attached to the vehicles with flexible hoses which must be attached when the vehicles are put into the building and detached when the vehicles are moved.
Many exhaust systems allow the hose to be moved along the length of a permanent exhaust duct even when connected to a vehicle's exhaust. In such systems a vehicle's emissions can be discharged outside even while the vehicle moves through the building, and they also permit the connection of hoses to vehicles of various sizes or in multiple locations. This movement of the hoses along an exhaust duct is generally accomplished by means of a duct which has a flexible seal to close a slot through which a pipe of a hose trolley extends into the duct. There are exhaust ducts with trolleys which are located overhead in buildings, and there are those built into the floor of a building which use trolleys rolling on the floor.
Experience has shown that the overhead exhaust trolleys require larger blowers for the use by vehicles with exhaust systems at the bottom of the vehicle because they require long hoses which increase the load on the exhaust system. Furthermore, manually attaching a flexible hose to the end of an exhaust outlet pipe located at the top of a vehicle can be time consuming, difficult, and even dangerous.
On the other hand, while exhaust trolleys at ground level are particularly convenient to use for vehicles with exhaust pipes located at the bottom of the vehicle, they have the same difficulty in attachment to exhaust pipes which are located at the top of a vehicle.
It would be very beneficial to have a device which would permit attaching a flexible hose to a vehicle exhaust system approximately at ground level even for a vehicle whose exhaust discharged near the top of the vehicle.